1. Field of the Invention
The present invention relates to the maintenance of flue stacks and the like to keep them in sufficiently clean condition, particularly those flues through which grease-laden air passes, such as for example those which exist in commercial restaurant kitchens and the like which must be regularly cleaned of any greasy deposits for sanitary and safety purposes, and more particularly the present invention relates to a maintenance system which includes a replaceable liner which is applied to the flue by means of ballooning air pressure applied to the interior of the liner which is originally inserted in a relative compact disposition.
2. Prior Art
A problem which is of continuous maintenance concern is the maintaining of flues, in for example commercial restaurant kitchens, free of large, greasy deposits which occur on the interior of the flue, and if allowed to build up too much, can cause sanitary problems and also safety problems because of the inherent fire hazard involved.
Heretofore, it has been necessary to have the interior wall surfaces of such flues maintained by the commercial establishment's staff or by an outside cleaning service, who, after dismantling the entry and exit portions of the flue stack, clean the interior surfaces in a scrubbing process utilizing appropriate chemical, detergent agents. This process of course is quite dirty, time consuming and relatively expensive and also produces considerable down-time of the cooking facilities associated with the flue stack.
Likewise in the home such prior art cleaning techniques usually required employing expensive sweeps, hours of inconvenience, and damage to furniture, carpets and walls due to the soot settling during cleaning.
The present invention is directed to overcoming and resolving these prior art problems with an efficient, quickly applied, reliable and relatively inexpensive system which produces relatively no mess or fuss in comparison to the techniques of the prior art.
A tabular listing of prior U.S. patents known to applicant which may be of interest to the present invention is presented below:
______________________________________ Inventor(s) Patent No. Issue Date ______________________________________ A. C. Badger 895,412 August 11, 1908 Pierre Thivans 3,897,619 August 5, 1975 H. V. Ludwick 2,086,134 July 6, 1937 R. R. Pierce Et al 3,367,075 Feb. 6, 1968 John R. Roy 3,537,411 Nov. 3, 1970 ______________________________________
It is noted that the Badger patent discloses the use of very high internal air pressure (100 lbs./sq. in.) in applying and bonding in association with heat a layer of lead or zinc through two solder coatings to the interior of a steel cylindrical receptacle.
The Thivans patent discloses the use of fluid pressure for placing a connecting sleeve between two pipe sections.
The Ludwick patent discloses a method of making a tank for a tank truck in which interior hydraulic pressure is used to cause flat metal sheets to conform to the interior cylindrical surface of the tank which sheets are then held in place with reinforcing bands.
The Pierce et al. patent discloses the use of a fluorocarbon plastic membrane which is applied in sheet form like a bandage to a chimney wall to serve as a corrosion proof liner.
The Roy patent discloses the use of a double shelled chimney stack made up of a load bearing outer metal shell and a non-load bearing inner metal shell with a sealed, insulating annular air space between them.
However, it is believed clear that none of these prior patents singly or in combination fairly teach or suggest the present invention.